BALTIMORE (AP) — Maryland's highest court on Thursday heard arguments in the high-profile case of a man whose murder conviction was chronicled in the hit "Serial" podcast that attracted millions of armchair detectives.

A panel of seven judges with Maryland's Court of Appeals heard about an hour's worth of arguments from the state and the defense in Adnan Syed's long-running case, reviewing a decision that could reinstate Syed's conviction for the slaying of his high school sweetheart. He was convicted in 2000 of strangling 18-year-old Hae Min Lee and burying her body in a Baltimore park. He's been serving a life sentence ever since.

But a Baltimore judge vacated his conviction two years ago and a court ordered a new trial after concluding that his trial lawyer was ineffective. The state appealed. Earlier this year, the special appeals court upheld the lower court's ruling. The state appealed that decision, too.

State prosecutor Thiru Vignarajah on Thursday acknowledged that the late trial lawyer for Syed did not contact a key alibi witness but he asserts that the attorney understood the "gist" of what that witness, Asia McClain, might have told her at the time. The attorney in question, Cristina Gutierrez, died of a heart attack in 2004, about four years after Syed was convicted of murder.

"The record is not silent on whether or not Ms. McClain was contacted. The state agrees with that. The record is silent on the critical question of why," he said, suggesting that it is not clear why Gutierrez decided to take one investigative path over another and asserting that it's wrong to conclude that Syed's constitutional right to effective counsel was violated.

Two years ago, a lower court ordered a retrial for Syed on grounds that Gutierrez didn't contact McClain and provided ineffective counsel.

The defense team countered that it's entirely irrelevant why Gutierrez failed to contact McClain, an alibi witness who said she saw Syed at a library about the same time prosecutors say his ex-girlfriend was killed in 1999.

Defense attorney Catherine Stetson told Maryland's highest court that Syed's original lawyer's failure to contact the witness were "objectively unreasonable" and any possible reasons don't matter. She said Gutierrez "had an obligation to pursue that witness," among others.

By late Thursday morning, the Annapolis court wrapped up the day's oral arguments in their review of the case. It's not clear when the panel's review of the Syed case will be completed.

University of Baltimore law professor David Jaros said the fact that a lower court had found that there was "ineffective assistance of counsel" was itself remarkable since it happens so rarely. That alone makes Syed's case something of an outlier, he said.

"Ineffective assistance of counsel claims are exceedingly hard to bring. And the bar for what is an effective assistance of counsel is remarkably and shockingly low, with courts actually holding that defendants had effective representation even though their lawyer fell asleep at the trial," Jaros said in a phone interview.

But what also makes Syed's case notable is the huge amount of attention it has received. Syed became a sort of cause celebre due to the hugely popular "Serial" podcast, which debuted in 2014 with its entire first season dedicated to the case.

The show shattered podcast-streaming and downloading records. "Serial" revealed little-known evidence, raising new questions about the case and whether Syed was indeed guilty.

Charlene and Lyman Smith pose for a photo at his class reunion at San Juan High School in Citrus Heights, Calif. The married couple were found dead in March 1980 in their Ventura home. Courtesy of Jennifer Carole

Claude Snelling, a journalism professor at College of the Sequoias in Visalia, Calif., in his classroom before he was killed Sept. 11, 1975, saving his daughter from a kidnapper. Courtesy of Elizabeth Hupp